3D printing is more accessible than ever with costs coming down and new printer manufacturers popping up every day. There are printers that a hobbyist could easily afford ten of, or there are powerhouse printers built to handle the needs of an established manufacturing firm. Identifying which 3D printer is right for you can easily give you a case of analysis paralysis - with so many options available, it’s easy to feel overwhelmed - there are printers that can handle advanced materials like PEEK, TPU, or Polycarbonate, yet others that won’t be able to print with more common materials like PLA, PETG or ASA. There are also types of printers to consider, like FDM, FFF, SLA, MSLA, or DLP. We’re here to help break down the different kinds of 3D printers and their capabilities - let’s get started with the basics.

What is 3D printing?

In terms of desktop 3D printing, there are two options: the plastic melting kind or the liquid resin kind. The plastic melting is called FDM or FFF, and it works on the basis of feeding thermoplastic into a hot nozzle, melting it down, and precisely laying it out. When a 3D printer uses liquid resin (called SLA, DLP, or MSLA depending on specific construction), it utilizes specific formulations of resin that are reactive to select wavelengths of light, which means a small light source within the 3D printer is solidifying the resin it passes over. These two methods are similar in that they are printing in 3 dimensions, but there are plenty of differences in uses, their strengths, and their weaknesses. For simplicity, I will refer to plastic based printers as FFF and resin based printers as SLA.

FFF is fantastic for demonstration models showcasing the inner workings of different machinery.
FFF is fantastic for demonstration models showcasing the inner workings of different machinery.

FFF: Fused Filament Fabrication

FFF 3D printers, the plastic melters, are the most common form of 3D printing as the material science already exists for plastics, making it an easy transition into the additive manufacturing space. Generally, FFF 3D printers are better geared toward users that are looking for specific material choices and specifications based on plastics commonly used in manufacturing, like nylon, PETG, or ABS. This does tend to mean FFF 3D prints tend to be stronger than SLA 3D prints, especially when FFF materials can be infused with things like carbon fiber or kevlar. Between FFF and SLA printers, you’re going to be able to find a lot more shapes and sizes with FFF, with some printers as wide as 6” or 18” or as tall as 24” or as short as 6.” There’s also a lot more variance in pricing, with a fairly uniform distribution from really inexpensive but basic to expensive but well tuned. Think a regular sedan vs a sports car; one gets you from A to B, but the other will get you there in the smoothest ride of your life. 

FFF 3D printers comes in all shapes and sizes for a multitude of different use cases.
FFF 3D printers comes in all shapes and sizes for a multitude of different use cases.

SLA: StereoLithography Apparatus

SLA 3D printers, the liquid resin based printers, are unparalleled in their precision; where FFF printers will almost always have very obvious layer lines, SLA layers virtually disappear. Not only will SLA prints look cleaner than FFF prints with layers of the same thickness, a standard FFF nozzle is 0.4mm wide, which means details smaller than that get lost. With an SLA printer using a laser, the laser point can be 0.07mm wide (about the thickness of a human hair), which means all the tiny details of a model gets captured. This does, however, come at the cost of print time. SLA printers tend to be smaller, have more expensive material costs (as the science of making a liquid cure only under specific conditions and not just “solid when cold, runny when hot” is a lot more difficult), and more limitations on the usable materials (like standard resin, resin with a little ductility, flexible resin, or even investment casting resin), but this can all be a worthwhile tradeoff to achieve this level of detail. Some of the most common SLA 3D prints I’ve seen are miniature figurines or prototypes nearing a final product. These are only some of the excellent uses of SLA 3D printers.

There is an absurd amount of detail that can be captured utilizing an SLA 3D printer.
There is an absurd amount of detail that can be captured utilizing an SLA 3D printer.

Making a decision on a new and constantly developing technology can be challenging, but it doesn’t need to be. Hopefully with this primer, you will have a better direction to finding the right printer for you, and remember, you always have the expert team at MatterHackers that you can email or call to help set you on the path for success. If you want to learn more about the inner workings of 3D printers, check out our series of articles about the Anatomy of a 3D Printer.